logstash-plugins/logstash-filter-json — pull request #3 by talevy (2014-12-19 20:13:37+00:00)
Title: add check for json filter to see if input codec already loaded the json

originally discovered to be incompatible when using the json input codec, as it has already called `LogStash::Json.load` on the whole input. (ref: https://github.com/elasticsearch/logstash/issues/2199)